2017-09-26T21:39:54ZCladogenesis and endemism in Tanzanian mole-rats, genus Fukomys: (Rodentia: Bathyergidae): a role for tectonics?http://www.suaire.suanet.ac.tz:8080/xmlui/handle/123456789/1449
Cladogenesis and endemism in Tanzanian mole-rats, genus Fukomys: (Rodentia: Bathyergidae): a role for tectonics?
Faulkes, C.G; Mgode, G.F.; Le Comber, S.C.; Bennett, N.C
African mole-rats of the family Bathyergidae are subterranean hystricomorph rodents found throughout sub-
Saharan Africa, where the distributional ranges of the most speciose taxa are divided by the African Rift Valley.
In particular, mole-rats of the genera Heliophobius and Fukomys are distributed widely, and their adaptive
radiation appears to have been strongly influenced by the geological process of rifting. As a result, virtually all
members of the genus Fukomys occur in locations west of the Rift Valley. However, a small number of isolated
populations occur east of the Rift Valley in Tanzania, where Heliophobius is widespread and is the predominant
bathyergid rodent. Phylogenetic analysis of mitochondrial cytochrome b sequences of previously unstudied
Tanzanian mole-rats (genus Fukomys) and geographically adjacent populations strongly suggests that vicariance
in the Western Rift Valley has subdivided populations of mole-rats and, together with climatic changes, played a
role in the isolation of extralimital populations of Fukomys in Tanzania. Together with molecular clock-based
estimates of divergence times, these results offer strong support for the hypothesis that the observed patterns of
cladogenesis are consistent with tectonic activity in the ‘Mbeya triple junction’ and Rungwe volcanic province
between Lakes Rukwa and Nyasa.
Biological Journal of the Linnean Society, 2010; 100: 337–352.
2010-01-01T00:00:00ZBreeding seasonality and population dynamics of three rodent species in the Magamba Forest Reserve, Western Usambara Mountains, north-east Tanzaniahttp://www.suaire.suanet.ac.tz:8080/xmlui/handle/123456789/1446
Breeding seasonality and population dynamics of three rodent species in the Magamba Forest Reserve, Western Usambara Mountains, north-east Tanzania
Makundi, R. H.; Massawe, A. W.; Mulungu, L. S.
We investigated breeding seasonality and population
dynamics of three rodent species, Lophuromys flavopuncatus,
Grammomys dolichurus and Praomys delectorum, in the
Magamba Forest, Western Usambara Mountains, northeast
Tanzania. Capture–mark–recapture studies were conducted
in 2002–2004. Reproductive conditions of males
and females showed temporal variations, an indication of
breeding seasonality. Animals were reproductively active
between February and May. Rainfall in November–January
was instrumental for the onset of breeding and continued
throughout the wet season. The recruitment of new individuals
born during the season led to highest population
densities between end of May and August. Populations
declined progressively towards the end of the dry season
(September–October). Only P. delectorum showed a marked
density increase during January–February, indicating
greater survival and/or recruitment during the November–
January rains. The study shows that despite a relatively
stable environment of the forest reserve, rainfall has strong
influence on reproduction and population dynamics,
probably because of its effect on primary food resources.
Key words: breeding, dynamics, Grammomys, Lophuromys,
Praomys, Tanzania
Re´sume´
Nous avons e´tudie´ la chronologie saisonnie`re de la reproduction
et la dynamique de la population de trois espe`ces de
rongeurs, Lophuromys flavopunctatus, Grammomys dolichurus
et Praomys delectorum, dans la foreˆt de Magamba, dans
la partie ouest des monts Usambara, au nord-est de la
Tanzanie. Des e´tudes par capture – marquage – re-capture
ont e´te´ re´alise´es en 2002 – 2004. La condition reproductrice
des maˆles et des femelles pre´sentait des variations
saisonnie`res, un indice de saisonnalite´ de la reproduction.
Les animaux e´taient en e´tat de reproduction active entre
fe´vrier et mai. Les chutes de pluie de novembre a` janvier
e´taient tre`s importantes pour le de´clenchement de la
reproduction et continuaient pendant toute la saison des
pluies. Le recrutement de nouveaux individus ne´s durant
cette saison conduisait a` une densite´ de population qui
culminait entre fin mai et aouˆ t. Les populations de´clinaient
progressivement jusque vers la fin de la saison se`che (septembre
– octobre). Seul P. delectorum montrait un taux de
recrutement et/ou de survie plus e´leve´ pendant les pluies de
novembre a` janvier. Cette e´tude montre que malgre´ l’environnement
relativement stable de la re´serve forestie`re, les
chutes de pluie ont une forte influence sur la reproduction
et la dynamique des populations, probablement a` cause de
leur effet sur les ressources primaires en nourriture.
2006-01-01T00:00:00ZChallenges in determining the pathogenicity status of Leptospira isolates with phenotypic methods: The need for a polyvalent approachhttp://www.suaire.suanet.ac.tz:8080/xmlui/handle/123456789/1443
Challenges in determining the pathogenicity status of Leptospira isolates with phenotypic methods: The need for a polyvalent approach
Mgode, G. F.; Machang’u, R. S.; Collares-Pereira, M.; Vieira, M. L.; Goris, M. G. A.; Engelbert, M.; Hartskeerl, R. A.
Understanding the pathogenic status of leptospires, the causative agents of leptospirosis, is important
for successful laboratory diagnosis and control programmes of this zoonosis. Leptospires are difficult
to differentiate morphologically; therefore, their pathogenic, intermediate or saprophytic status is
currently determined based on both phenotypic tests like growth response in medium containing
8-azaguanine and growth at low temperature (13°C), and genotypic methods. The present study reports
on the pathogenic versus saprophytic characterization of nine Leptospira isolates from animal hosts
(rodents and dogs) and humans, with specific interest on a canine isolate coded “Dog109”, which
showed an ambiguous or intermediate status according to conventional (phenotypic) and molecular
(genotypic) tests. The results strongly indicate the need of a polyvalent analytical approach for
improving the differentiation of the pathogenic status of circulating serovars,
African Journal of Microbiology Research, 2010; 4 (23): 2528-2533
2010-12-04T00:00:00ZApplication of a multidisciplinary approach to the systematics of Acomys (Rodentia: Muridae) from Northern Tanzaniahttp://www.suaire.suanet.ac.tz:8080/xmlui/handle/123456789/1433
Application of a multidisciplinary approach to the systematics of Acomys (Rodentia: Muridae) from Northern Tanzania
Mgode, G. F.
The systematic status and geographic distribution of spiny mice of the genus Acomys I.
Geoffroy, 1838 in Northern Tanzania is uncertain. This study assesses the systematic and
geographic distribution of Acomys from Northern Tanzania using a multidisciplinary
approach that includes molecular, cytogenetic, traditional and geometric morphometric
analyses, and classical morphology of the same individuals. The molecular analysis was
based on 1140 base pairs (bp) of the mitochondrial cytochrome b and 1297 bp of the
nuclear interphotoreceptor retinoid binding protein (IRBP) gene sequences. These data
were subjected to phylogenetic analyses using Maximum likelihood, Bayesian, Maximum
parsimony, and Minimum evolution analyses. The cytogenetic analysis included G-banding
of metaphase chromosomes. The morphometric analyses included univariate and
multivariate analyses of traditional morphometric measurements of the cranium and
mandible, and of geometric morphometric two-dimensional landmarks of the dorsal,
ventral, and lateral views of the cranium, and lateral view of mandible that included thinplate
spline (TPS) analysis. The classical morphology included examination of external,
cranial and mandibular morphology. Results of all these multidisciplinary analyses were
congruent and provide evidence for the occurrence of two sympatric species of Acomys in
northern Tanzania, namely, the previously recorded A. wilsoni (2n = 62) and a newly
recorded A. cf. percivali (2n = 58). These results that also represent the first reported
mitochondrial cytochrome b and nuclear IRBP gene sequences and karyotype for A. cf.
percivali, increases the number of species known to occur in Tanzania from four to five.
However, the mitochondrial cytochrome b data that included GenBank sequences from the
type locality in Kenya suggest that A. wilsoni may not be monophyletic. Ecologically, the
two species seem to partition their niches with A. cf. percivali being found in well-covered
habitats with thorn bushes, rocky and mountainous areas, and A. wilsoni being found in
open semi-arid grasslands as well as in rice fields. The two species appear to be isolated by
complex natural barriers formed by the Great East African Rift Valley whose geological
features have generally been associated with active rodent speciation. However, the present
results need further multidisciplinary investigation involving extensive sampling and
examination of topotypical material.
2006-12-01T00:00:00Z